CVE-2021-47024: linux kernel — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: free queued packets when closing socket As reported by syzbot [1], there is a memory leak while closing the socket. We partially solved this issue with commit ac03046ece2b ("vsock/virtio: free packets during the socket release"), but we forgot to drain the RX queue when the socket is definitely closed by the scheduled work. To avoid future issues, let's use the new virtio_transport_remove_sock() to drain the RX queue before removing the socket from the af_vsock lists calling vsock_remove_sock(). [1] https://syzkaller.appspot.com/bug?extid=24452624fc4c571eedd9

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-401 CWE-401

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.2 — 5.10.37
linux	linux_kernel	5.11 — 5.11.21
linux	linux_kernel	5.12 — 5.12.4

References

Advisories & Patches

https://git.kernel.org/stable/c/27691665145e74a45034a9dccf1150cf1894763a https://git.kernel.org/stable/c/37c38674ef2f8d7e8629e5d433c37d6c1273d16b https://git.kernel.org/stable/c/8432b8114957235f42e070a16118a7f750de9d39 https://git.kernel.org/stable/c/b605673b523fe33abeafb2136759bcbc9c1e6ebf https://git.kernel.org/stable/c/27691665145e74a45034a9dccf1150cf1894763a https://git.kernel.org/stable/c/37c38674ef2f8d7e8629e5d433c37d6c1273d16b https://git.kernel.org/stable/c/8432b8114957235f42e070a16118a7f750de9d39 https://git.kernel.org/stable/c/b605673b523fe33abeafb2136759bcbc9c1e6ebf

Frequently Asked Questions

What is CVE-2021-47024? +

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: free queued packets when closing socket As reported by syzbot [1], there is a memory leak while closing the socket. We partially solved this issue with commit ac03046ece2b ("vsock/virtio: free packets during the socket release"), but we forgot to drain the RX queue when the socket is definitely closed by the scheduled work. To avoid future issues, let's use the new virtio_transport_remove_sock() to drain the RX queue before removing the socket from the af_vsock lists calling vsock_remove_sock(). [1] https://syzkaller.appspot.com/bug?extid=24452624fc4c571eedd9 It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-47024? +

CVE-2021-47024 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2021-47024? +

CVE-2021-47024 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2021-47024? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2021-47024